z-logo
Premium
A consistency proof for some restrictions of Tait's reflection principles
Author(s) -
McCallum Rupert
Publication year - 2013
Publication title -
mathematical logic quarterly
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.473
H-Index - 28
eISSN - 1521-3870
pISSN - 0942-5616
DOI - 10.1002/malq.201200015
Subject(s) - reflection (computer programming) , consistency (knowledge bases) , mathematics , set (abstract data type) , combinatorics , order (exchange) , discrete mathematics , computer science , finance , economics , programming language
In 5, Tait identifies a set of reflection principles called \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\Gamma ^{(2)}_{n}$\end{document} ‐reflection principles which Peter Koellner has shown to be consistent relative to the existence of κ(ω), the first ω‐Erdős cardinal 1. Tait also defines a set of reflection principles called \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\Gamma ^{(m)}_{n}$\end{document} ‐reflection principles; however, Koellner has shown that these are inconsistent when m > 2, but identifies restricted versions of them which he proves consistent relative to κ(ω) 2. In this paper, we introduce a new large‐cardinal property, the α‐reflective cardinals. Their definition is motivated by Tait's remarks on parameters of third or higher order in reflection principles. We prove that if κ is ℶ κ + α + 1 ‐supercompact and 0 < α < κ then κ is α‐reflective. Furthermore we show that α‐reflective cardinals relativize to L, and that if κ(ω) exists then the set of cardinals λ < κ(ω), such that λ is α‐reflective for all α such that 0 < α < λ, is a stationary subset of κ(ω). We show that an ω‐reflective cardinal satisfies some restricted versions of \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\Gamma ^{(m)}_{n}$\end{document} ‐reflection, as well as all the reflection properties proved consistent in 2.

This content is not available in your region!

Continue researching here.

Having issues? You can contact us here
Accelerating Research

Address

John Eccles House
Robert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom